Buffing machine



R. D. HARRIS BUFFING MACHINE Nov. 9, 1948.

4 Sheets-Sheet 2 Filed 0911.*2, 1946 Snve'ljtor RnberBHarrzs gam @fi/#Gimmy R. D. HARRIS BUFFING MACHINE Nov. 9, 1948.

Filed vom. 2, 194e 4 Sheets-Sheet '3 @fieri/B11123328 n y y I I (ttornegs NOV. 9,1948. R D; HARR|$ 2,453,316

BUFFING- MACHINE Filed oct. 2, 1946 4 sheet's-shget 4 l g o 1 W INV I .90 a 75 u FL 70 [l ji :pz/45 -A '1 -j' E 9,? 'y 91 Il i Fig: 8 y Fi 91 i] V 4 y Stwentgr RoberiBHarrzs Gttomegs Patented Nov. 9, 1948 BUFFING MACHINE Robert D. Harris, Massillon, Ohio, assignor to The Enterprise Aluminum Company, Massillon, Ohio, a corporation of Ohio Application October 2, 1946, Serial No. 700,726

The invention relates to hurling machines and more particularly to a machine for buiiing hollow sheet metal ware such as aluminum cooking utensils and the like.

-The object of the invention -is rto provide an l apparatus including a rotatable chuck for receiving hollowware to be buied, a rotatable bufng wheel, means for moving the chuck relative to the bufling wheel to bring the ware into contact therewith and means for returning the chuck to initial position spaced from the bufng wheel when the bufiing operation is completed.

Another object is to provide a cam operated pressure pad for automatic movement toward the chuck when the chuck is moved to operative position relative to the bufling wheel, for holding the ware upon the chuck during the bufling operation.

A further object is to provide apparatus of this character in which the buing wheel is reciprocated axially during the buing operation, while the Ware is rotated upon a stationary aXis thus preventing the formation of grooves or lines in the buffed surface of the Ware.

A still further object is to provide cam means for reciprocating the bunng Wheel While the same is rotated.

Another object is to provide an apparatus of this character having a vertical slide casting carrying the Work holding chuck and the pressure pad.

A further object is to provide means for adjusting the vertical movement of the vertical slide casting.

A still further object is to provide means for angularly adjusting the vertical slide casting.

Another object is to provide fluid operated cylinders for operating the pressure pad and the vertical slide casting and a four-way valve for simultaneously operating both cylinders.

Still another object is to provide a slidable main drive bearing mounted in a horizontal slide base provided with eccentric cam and spring means for continually,reciprocating the same.

A further object is to provide an apparatus of this character in which the vertical slide casting carrying the ware holding chuck and the pressure pad is counter balanced upon the vertical frame of the machine and the nuid cylinder which operates the vertical slide casting is provided with a worm and screw adjustment for adjusting the throw of the vertical slide casting.

The abovel objects together with other which will be apparent for the drawing and following description or which may be later referred to,

14 Claims. (Cl. 51-50) may be attained by constructing the improved builing machine in the manner hereinafter described in detail and illustrated in the accompanying drawing in which:

Figure 1 is a front elevation of the improved hurling machine in the normal or intital position;

Fig. 2 a similar view showing the machine in the operated position;

Fig. 3 an enlarged, fragmentary plan sectional view of a portion of the slide base for the main drive and the slidable main drive bearing casting and the eccentric cam for reciprocating the same;

Fig. 4 an enlarged, transverse, vertical section through the slide base and the main drive;

Fig. 5 a side elevation of the machine in the initial position as shown in Fig. 1;

Fig. 6 a similar view in the operated position as shown in Fig 2;

Fig. 7 a fragmentary, horizontal, sectional View through the lworm screw and gear adjustment upon the shaft of the Vertical elevating cylinder;

Fig. 8 a side elevation, partly in section, of the vertical elevating cylinder and shaft showing the worm gear adjustably mounted upon the threaded upper end of the shaft;

Fig. 9 a side elevation of the cam which operates the pressure pad; n

Fig. l0 a longitudinal sectional View through the cam shown in Fig. 9 and the housing therefor;

Fig. 1l a front elevation of the vertical slide casting; and,

Fig. 12 afront elevation of the angularly adjustable spindle bearing casting for the work holding chuck.

The machine is assembled upon a horizontal bed or table l5 which may be supported at any suitable height above the floor as by the frame I6 and has nxed thereon at one end, the horizontally disposed channel shaped slide base I1 for the slidable main drive casting or bracket I8, upon opposite end portions of which are formed the upright main shaft bearings I9 and 28 through which is journalled the horizontal main drive shaft 2l.

A bufng wheel, formed of a plurality of discs of paper or the like, as in usual practice, is fixed upon the outer end portion of the main drive shaft 2|, beyond the outer end of the main drive casting or bracket I8, this buiilng Wheel being indicated generally at 22.

The paper discs are clamped together upon the shaft as by the metal washers or iiange plates 23 and 24 and the nut 25 located upon 3 the threaded outer end 26 of the main drive shaft.

The inner end of the main drive shaft 2! has a pulley 21 fixed thereon and preferably provided with a plurality of V-grooves 28 for receiving a plurality of V-belts 29 which are located over the drive pulley 3D upon the shaft 3! of the main drive motor 32, which is mounted upon the bed or table I at a point beyond the inner end of the slide base I1.

An eccentric cam 33 is xed upon the upper end of the vertical shaft 34 of the reducer 35, which is driven by the small motor 36 fixed to the under side of the bed or table, the cam 33 being held in contact with the inner or left hand end of the main drive casting or bracket by means of a plurality of coil springs 31 interposed between the bearing i9 of the main drive bracket and the cross bar 38 which is mounted in vertical position upon the machine being preferably fixed upon the top of the guide plates 39 which overhang the upper edges of the channel shaped slide base I1 and retain the main drive bracket I8 therein. Sockets 46 and 4! are provided in the main drive bearing I9 and the cross bar 38 respectively for housing opposite ends of the springs.

With this construction, as the motors 32 and 36 are operated the main drive shaft 2|, carrying the buing wheel 22, will be continually rotated through the pulley 30, belts 29 and pulley 21 and the eccentric cam 33 will be continually rotated through the motor 36 and reducer 35, the springs 3'! holding the sliding main drive bracket I8 in contact with the periphery of the cam 33 so that the main drive bracket and the bui-ling wheel 22 carried thereby will continually reciprocate in a horizontal plane, the belts 29 having sucient flexibility to permi-l of the longitudinal movement of the pulley 22 relative to the pulley 3D.

A vertical frame or, elevating casting 42 is xed upon the outer end portion of the bed or table l5, to the rear of the slide base I'! for the main drive bracket, and the vertical slide casting indicated generally at 43 is vertically slidably mounted and counter balanced by means of the chains or cables 44 connected to the upper end of the vertical slide casting 43, extending upward over the pulleys 45, journalled in brackets 46 upon the top of the vertical frame `42, and extending downward on the rear side thereof, the lower ends of said cables or chains being connected to the counter weight 41.

An angularly adjustable spindle bearing casting 48, for the spindle or the work holding chuck, is mounted upon the front of the vertical slide casting 43 and for the purpose of adjusting the same angularly upon the vertical slide casting, to accommodate tapered ware, the vertical slide casting 43 is provided with the vertically spaced horizontal upper and lower slots 49 and 5l! and the spindle bearing casting 48 is provided with the arcuate upper slot 5! and the lower aperture 52.

Bolts 53 and 54 are located through the arcuate slot 5! and upper horizontal slot 49 and through the aperture 52 and lower horizontal slot 50 to hold the spindle bearing bracket 48 in adjusted position upon the vertical slide casting 43.

The ware chuck spindle 55 is journalled through the bearing 56 in the spindle bearing casting and is operatively connected in conventional manner with a worm gear reducer located in the housing 51, which is driven by the small motor 58 mount-ed upon the .bracketI 48 so as to rotate the ware holding chuck 59 at desired relative speed andr preferably in opposite direction to the `bul'ing wheel 22.

The chuck 59 is removably mounted upon the spindle 55 in any conventional manner so that the chuck may .be easily removed and replaced as a different size and shape of chuck is required for each size and shape of hollow ware to be buied.

For the purpose of frictionally holding the hollow metal ware, indicated at W upon the chuck during the buing operation, a friction surface 60 of fabric or the like may cover the outside of the chuck for frictional contact with the interior of the hollow metal ware.

In order to hold the ware in proper position upon the chuck during the bung operation, a pressure block 6! is provided which is preferably formed of wood or the like, or cylindrical shape and preferably having'a pad 62 of felt or the like upon its at face adapted for contact with the bottom end of the hollow ware W.-

This block 6! is mounted upon a spindle 63 and may be rotatable thereon if desired. The spindle 63 is adjustably mounted, by means ofthe adjusting screw 64, upon the rodv 65 which is clamped, as by the bolt 66, into the end portion of the radial arm 61 of the angular casting 68 which is clamped upon the spindle 69 as lby the bolt 10.

The spindle 6 9, as best shown in Fig. l0, has a hollow cylindrical cam 1| xed thereon as by the set screws 12 and a cam groove 13 is formed in the outer surface of the cylindrical cam and comprises the central spiral portion 14 and the straight end portions 15 and 16.

This cylindrical cam is slidably and rotatably journalled within a bearing 1l', fixed uponthe vertical slide casting 43, and having ay pin 18 therein engaging the cam groove 13 so that as the cam 1I is longitudinally reciprocated through the bearing 11, the cam 1I and spindle 69 will be given a partial rotation.

The inner end of the spindle 69 is slidably located within a cylindrical housing 19 xed to the end of the piston rod 86 of the uid cylinder 8| and a head or shoulder 82 is vxed upon the inner end of the spindle 69, a coil spring 83 being interposed between said shoulder and the outer head 84 of the cylinder 19 so as to normally urge the spindle 69, and the parts carried thereby inward or toward the left relative to the cylinder 19.

The fluid cylinder 8! is a double acting cylinder, the opposite ends of which are connected by hose lines 85 and 86 with the four-way valve 81. Pressure fluid is admitted to the valve 81 through the pipe 88 leading from any suitable source of fluid pressure.

In the normal or initial position, as shown in Figs. l and 5, the radial arm 61 carrying the pressure block 6! is located outwardly at an angle so that the pressure block is raised above and located outwardly from the axis of the ware holding chuck l59.

Also in this position the spindle 69 carrying the pressure pad arm is located outwardly or to the right as viewed in Figs. l and 2 so that the pressure pad is located in a plane beyond the end of the ware holding chuck as best shown in Fig. l.

For the purpose of vertically reciprocating the vertical slide casting 43, an elevating screw 8'9 is suspended from the upper end of the elevating casting or frame 42 and has a fluid cylinder .90 connected t0 its lower end. The piston rod 9|. of

the cylinder extends through the lower head thereof and is connected to the ears 92 uponthe .rear side of the Vertical slide casting 43.

A hose line y93 connects the upper end of the cylinder 90 with the four-way valve 81. The counterk weight 41 normally holds the vertical slide casting 43 in the raised position, as shown in Fig. 5, and when the four-way Valve 81 is operated to admit uid to the upper end of lthe ycylinder -90 the piston rod 9| is forced downward .moving the vertical slide casting 43 downward -against the pull of the counter weight, to the -position shown in Figs. 2 and 6.

For the purpose of adjusting the throw of the `piston rod 9| to compensate for ware of varying diameters, the elevating screw 89 is threaded -through the elevating worm gear I94, journalled 4within the gear housing y95 in the upper end of the vertical frame or casting 42.

This worm gear is in mesh with the elevating worm screw 96; upon the elevating shaft 91 journalled in bearings `98 in the housing 95 and hav- ;ing a squared end 99 upon which a wrench or -other suitable tool may beplaced for rotating the lworm `96 and through it the worm gear -94 to raise or lower the elevating screw 89 and with lit the .fluid cylinder 99, to obtain the desired adjust- ,ment.4

yWith the machine in the initial position, as shown in Figs. 1 and 5, assuming that it is desired to operate the same to buff pieces of hollow metal ware such as indicated at W, the motors 32, 38 and 58 are operated causing the buifing lwheel 22 to be rapidly rotated and more slowly reciprocated horizontally, and causing the ware holding chuck 59 to ,be rotated at a different speed, or in the opposite direction to the bufng .wheel, or both.

An article of ware as indicated at W is placed upon the chuck 59 as shown in Fig. l and the four-way valve 81 is operated simultaneously operating the pistons in the fluid cylinders 8l and 90.

With the operation of the cylinder 8| the piston rod 69 thereof is drawn to the left as viewed in Fig. l, causing the pin 18 and cam slot 13 to rotate the spindle in counter clockwise direction as viewed in Figs. 5 and 6, moving the pressure pad 6I from the position shown in Figs. 1 and 5 to ,that shown in Figs. 2 and 6, bringing said pres.- ysure pad into axial alignment with the chuck and vat the same time moving it inward or to the left .so as to contact the bottom of the ware W upon Athe chuck and hold the same against displacement.

At the same 'time the operation ofthe fluid cylinder 490 will force the piston rod l9| thereof rdownward moving the vertical slide casting 43 downward bringing the rotating ware upon the chuck into contact with the periphery-offthe rotating and reciprocating bufling wheel 22 as shown in Figs. 2 and 6. l

The peripheral surface of the wareupon the chuck will be rapidly buied and polished,. and kdue to the continual reciprocation of the bufng wheel, there will be no circular lines or marks formed upon the surface of the ware. l Within a few seconds the ware is properly buifed when the four-way valve 81 may be operated in reversey direction, causing the -uid cylinder 8l to force its piston rod 80 outward or -to the rightand through the pin 18 and cam 1| swinging the pressure pad 6I upward and outward away from the chuck. 1 K- At the same time the iluid pressure in the ycylinder 90 is released permitting the counter weight 41 to raise the elevating casting 43 to the initial position shown in Figs. 1 and 5 when another piec'e of ware may be placed upon the chuck and the operation repeated.

I claim: i

1. A bufling machine for bulling hollow ware, including a lbu'ng wheel, means for rotating the buing wheel, means for axially reciprocating the bufng wheel while it is being rotated, a ware chuck adapted to receive hollow ware to be buffed, means for rotating said chuck, means for normally holding the chuck spaced fromthe bufng wheel, a pressure pad, means for normally holding the pressure pad spaced longitudinally and laterally from the chuck, and fluid pressure and cam means for simultaneously moving the pressure pad into Contact with the bottom of hollow ware upon the chuck and moving the chuck toward the buiiing wheel to bring the surface of the hollow ware upon the chuck into contact with the buing wheel. i

2. A buing machine for puffing hollow war including a buing wheel, means for rotating the buling wheel, cam means for axially reciprocating the bunng wheel while it is being rotated, 'a ware chuck adapted to receive hollow ware to be buffed, means for rotating said chuck, means for normally holding the chuck spaced from the bufling wheel, a pressure'pad, means for normally holding the pressure pad spaced longitudinally and laterally from the chuck, and means including a fluid pressure operated cam for simultaneously moving the pressure pad into contact with the bottom of hollow ware upon the chuck and moving the chuck toward the bufling wheel to bring the surface of the hollow ware upon the chuck into contact with the buling wheel.

3. A bufling machine for buing hollow ware, including a buffing wheel, means for rotating the bumng wheel, eccentric cam means for axially reciprocating the buing wheel while it is being rotated., a ware chuck adapted to receive hollow ware to be buffed, means for rotating said chuck, means for normally holding the chuck lspaced from the buinng wheel, a pressure pad, means for normally holding the pressure pad spaced longitudinally and laterally from the chuck, and iiuid pressure means for moving the pressure pad into contact with the bottom of hollow Ware upon the chuck and fluid pressure means for moving the chuck toward the buing wheel to bring the surface of the hollow ware upon the chuck into contact with the bufng wheel.

4. A hurling machine for bufling hollow ware, including a bufling wheel, means for rotating the bufng wheel, means for axially reciprocating the bufling lwheel while it is being rotated, a ware chuck adapted to receive hollow ware to be buffed, means for rotating said chuck, means for normally holding the chuck spaced from the buing wheel, -a pressure pad, means for normally holding the pressure pad spaced longitudinallyfand laterally from the chuck, and uid pressure means for moving the pressure pad into contact with the bottom of hollow ware upon the chuck and fluid pressure means moving the chuck toward the buing wheel to bring thesurface of fthe hollow ware upon the chuck into contact with the bufng wheel. l Y

5. A buing machine for bufng hollow ware, including a bufling wheel, means for rotating the bufling wheel, meansfor `axially reciprocating the bufhng wheel while it is being' rotated, a ware chuck adapted to receive hollow ware to be buried,

means for rotating said chuck, means for norh mally holding the chuck spaced from the buing wheel, a pressure pad, means for normally holding the pressure pad spaced longitudinally and laterally from the chuck, and means including a uid pressure operated cam for simultaneously moving the pressure pad into contact with the bottom of hollow ware upon the chuck and moving the chuck toward the buning wheel to bring the surface of the hollow ware upon the chuck into contact with the buiiing wheel.

6. A buiiing machine for buiiing hollow ware, including a buflng wheel, means for rotating the bufng wheel, means for axially reciprocating the bufng wheel while it is being rotated, a ware lchuck adapted to receive hollow ware to be buried, means for rotating sai-d chuck, means for normallyholding the chuck spaced from the bufting wheel, a pressure pad, means for normally holding the pressure pad spaced from the chuck, and iiuidpressure and cam means for simultaneously moving the pressure pad into contact with the bottom of hollow ware upon the chuck and moving the chuck toward the bufiing wheel to bring the surface of the hollow ware upon the chuck into cont-act with the bufng wheel.

'7. A buiiing machine for buiiing hollow ware, including a buffing wheel, means for rotating the hurling wheel, means for axially reciprocating the buing wheel while it is being rotated, a ware chuck adapted to receive hollow ware to be bulied, means for rotating said chuck, means for normally holding the chuck spaced from the buing wheel, a pressure pad, means for normally holding the pressure pad spaced from the chuck, fluid cylinder operated means for moving the pressure pad into contact with the bottom of the hollow ware upon the chuck, a second fluid cylinder operated means for moving the chuck toward the buffmg wheel to bring the surface of the hollow ware upon the chuck into contact with the bulng wheel, and a four-way valve for simultaneously operating both of the iiuid cylinders.

8. A buinng machine for buffing hollow ware, including a buing wheel, means for rotatingthe buihng wheel, means for axially reciprocating the hurling wheel While it is being rotated, a ware chuck adapted to receive hollow ware to be bullied, means for rotating said chuck, means for normally holding the chuck spaced from the buing wheel, a pressure pad, means for normally holding the pressure pad spaced from the chuck, fluid cylinder operated .means including a cam for moving the pressure pad into contact with the bottom of the hollow ware upon the chuck, a second fluid cylinder operated means for moving the chuck toward the bufiing wheel to bring the surface of the hollow ware upon the chuck into contact with the b-uing wheel, and a four-way valve for simultaneously operating both of the fluid cylinders.

9. Abuffing machine for buffing hollow ware, including a slide base, a bearing bracket slidable on- 'said slide base, a shaft journalled in said bearing bracket, a buffing wheel upon said shaft, means for rotating said shaft, a cam operatively engaging the bearing bracket, means for rotating said cam to reciprocate said bearing bracket, a ware chuck adapted to receive hollow ware to be buied, means for rotating said chuck, means for normally holding the chuck spaced from the buiing wheel, a pressure pad, means for normally holding the pressure pad spaced longitudinally and laterally from the chuck, fluid cylinder operated means for moving the pressure pad into `contact with the bottom of hollowr ware upon the chuck and second fluid cylinder operated means for moving the chuck toward the buffin'gA wheel to bring the surface yof the hollow ware upon the chuck into contact with the buling wheeland a valu-e for simultaneously operating both of the uid cylinders. v

l0. A buifing machine for buffing hollow ware, including a slide base, a bearing bracket slidable on said slide base, a shaft'journalled in said bearing bracket, a buffing wheel upon said shaft, means for rotating said shaft, a cam operatively engaging the bearing bracket,l spring means for holding the bearing bracket in contact with the cam, means for rotating said cam to reciprocate said bearing bracket, a ware chuck adapted to receive hollow ware to be klouiifed, means for ro'- tating said chuck, means for normally holding the chuck spaced from the buffing wheel, a pres"- sure pad, means for normally holding the pressure pad spaced from the chuck, and means for simultaneously moving the pressure pad in'to contact with the bottom of hollow ware upon the chuck and moving the chuck toward the buffi'ng Wheel to bring the surface of the hollow ware upon `the chuck into contact with the buing wheel.-

l1. A buffing machine for buifing hollow ware, including a buliing wheel, means for rotating the. bufing wheel, means for axially reciprocating the buffing wheel while it is being rotated, a ware chuck adapted to receive hollow ware'to be bue'd,

means for angularly adjusting the chuck relative` tothe buffing wheel, means for rotating said chuck, means for normally holding; the chuck spaced from the 'puffing-wheel, a pressure `pad, means for normally holding the pressure pad spaced longitudinally and laterally from the chuck, fluid cylinder operating mean's'f'or moving the pressure pad into Contact with the bottom of hollow ware upon the chuck and a second` fluid cylinder operated lmeans for moving the chuck toward the buffing wheel to bring the surface of the hollow ware upon the chuck into contact with the buffing wheel and a value for simultaneously'operating both of `the uid cylinders.

12. A buffing machine for buffing hollow ware, including a bed, a horizontally disposed slide base upon the bed, a bearing bracket slidable upon said slide base, a shaft journalled in said bearing bracket, a buifing wheel upon said shaft, means for rotating said shaft, an eccentric'cam operatively engaging said bearing bracket, means for rotating said cam to reciprocate said bearing bracket, a Vertical frame mounted upon the bed, a vertical slide casting slidable upon said vertical frame, counter-weight means for normally hold ing the vertical slide casting in raised position, a uid cylinder for lowering the vertical slide casting, a ware chuck journalled upon said vertical slide frame for receiving hollow ware, a `spin'-v dle slidably and rotatably mounted upon said Vertical slide casting, cam means for rotating the spindle upon its axis when it is moved axially/,a uid cylinder for axially moving the spindle,- a radial arm carried by the spindle, a pressure pad upon said radial arm normally located spaced fron the chuck, and means for operating said. fluid cylinders for moving the pressure pad into contact with the bottom of the hollow ware upon the chuck and for moving the chuck toward the buffing wheel to bring the surface of the hollow ware upon the chuck into contact with the buiing wheel.

13. A buing machine for bufling hollow ware..

including a bed, a horizontally disposed slide base upon the bed, a bearing bracket slidable upon said slide base, a shaft journalled in said bearing bracket, a buing wheel upon said shaft, means for rotating said shaft, an eccentric cam operatively engaging said bearing bracket, means for rotating said cam to reciprocate said bearing bracket, a vertical frame mounted upon the bed, a Vertical slide casting slidable upon said vertical frame, counter-weight means for normally holding the vertical slide casting in raised position, a fluid cylinder for lowering the vertical slide casting, a ware chuck journalled upon said vertical slide frame for receiving hollow ware, a spindle sldably and rotatably mounted upon said vertical slide casting, cam means for rotating the spindle upon its axis when it is moved axially, a fluid cylinder for axially moving the spindle, a radial arm carried by the spindle, a pressure pad upon said radial arm normally located spaced from the chuck, and a four-way valve for simultaneously operating said fluid cylinders for moving the pressure pad into contact with the bottom of the hollow ware upon the chuck and for moving the chuck toward the bufng Wheel to bring the surface of the hollow ware upon the chuck into contact with the bufling wheel.

14. A buiiing machine for buiiing hollow Ware, including a bed, a horizontally disposed slide base upon the bed, a bearing bracket slidable upon said slide base, a shaft journalled in said bearing bracket, a buiiing wheel upon said shaft, means for rotating said shaft, an eccentric cam operatively engaging said bearing bracket, means for rotating said cam to reciprocate said bearing bracket, a vertical frame mounted upon the bed,

a vertical slide casting slidable upon said vertical frame, counter-weight means for normally holding the vertical slide casting in raised position, a fluid cylinder for lowering the vertical slide casting, a ware chuck journalled upon said vertical slide frame for receiving hollow ware, means for angularly adjusting the chuck relative to the buiiing Wheel, a spindle slidably and rotatably mounted upon said Vertical slide casting, cam means for rotating the spindle upon its axis when it is moved axially, a fluid cylinder for axially moving the spindle, a radial arm carried by the spindle, a pressure pad upon said radial arm normally located spaced from the chuck, and means for operating said uid cylinders for moving the pressure pad into contact with the bottom of the hollow ware upon the chuck and for moving the chuck toward the bufng wheel to bring the surface of the hollow ware upon the chuck into contact with the buiiing wheel.

ROBERT D. HARRIS.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 835,320 Pomeroy Nov. 6, 1906 1,115,640 Winter Nov. 3, 1914 1,477,426 Carlson Dec. 11, 1923 1,509,904 Salisbury Sept. 30, 1924 1,515,640 Wheaton Nov. 18, 1924 2,161,947 Bower June 13, 1939 2,331,089 Flygare et al Oct. 5, 1943 

